# Copyright 2014 IBM Corp.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import abc
from oslo_config import cfg
from oslo_log import log
import six
from keystone.common import dependency
from keystone.common import manager
from keystone import exception
from keystone.i18n import _, _LE, _LW
CONF = cfg.CONF
LOG = log.getLogger(__name__)
@dependency.provider('endpoint_policy_api')
@dependency.requires('catalog_api', 'policy_api')
class Manager(manager.Manager):
"""Default pivot point for the Endpoint Policy backend.
See :mod:`keystone.common.manager.Manager` for more details on how this
dynamically calls the backend.
"""
driver_namespace = 'keystone.endpoint_policy'
def __init__(self):
super(Manager, self).__init__(CONF.endpoint_policy.driver)
def _assert_valid_association(self, endpoint_id, service_id, region_id):
"""Assert that the association is supported.
There are three types of association supported:
- Endpoint (in which case service and region must be None)
- Service and region (in which endpoint must be None)
- Service (in which case endpoint and region must be None)
"""
if (endpoint_id is not None and
service_id is None and region_id is None):
return
if (service_id is not None and region_id is not None and
endpoint_id is None):
return
if (service_id is not None and
endpoint_id is None and region_id is None):
return
raise exception.InvalidPolicyAssociation(endpoint_id=endpoint_id,
service_id=service_id,
region_id=region_id)
def create_policy_association(self, policy_id, endpoint_id=None,
service_id=None, region_id=None):
self._assert_valid_association(endpoint_id, service_id, region_id)
self.driver.create_policy_association(policy_id, endpoint_id,
service_id, region_id)
def check_policy_association(self, policy_id, endpoint_id=None,
service_id=None, region_id=None):
self._assert_valid_association(endpoint_id, service_id, region_id)
self.driver.check_policy_association(policy_id, endpoint_id,
service_id, region_id)
def delete_policy_association(self, policy_id, endpoint_id=None,
service_id=None, region_id=None):
self._assert_valid_association(endpoint_id, service_id, region_id)
self.driver.delete_policy_association(policy_id, endpoint_id,
service_id, region_id)
def list_endpoints_for_policy(self, policy_id):
def _get_endpoint(endpoint_id, policy_id):
try:
return self.catalog_api.get_endpoint(endpoint_id)
except exception.EndpointNotFound:
msg = _LW('Endpoint %(endpoint_id)s referenced in '
'association for policy %(policy_id)s not found.')
LOG.warning(msg, {'policy_id': policy_id,
'endpoint_id': endpoint_id})
raise
def _get_endpoints_for_service(service_id, endpoints):
# TODO(henry-nash): Consider optimizing this in the future by
# adding an explicit list_endpoints_for_service to the catalog API.
return [ep for ep in endpoints if ep['service_id'] == service_id]
def _get_endpoints_for_service_and_region(
service_id, region_id, endpoints, regions):
# TODO(henry-nash): Consider optimizing this in the future.
# The lack of a two-way pointer in the region tree structure
# makes this somewhat inefficient.
def _recursively_get_endpoints_for_region(
region_id, service_id, endpoint_list, region_list,
endpoints_found, regions_examined):
"""Recursively search down a region tree for endpoints.
:param region_id: the point in the tree to examine
:param service_id: the service we are interested in
:param endpoint_list: list of all endpoints
:param region_list: list of all regions
:param endpoints_found: list of matching endpoints found so
far - which will be updated if more are
found in this iteration
:param regions_examined: list of regions we have already looked
at - used to spot illegal circular
references in the tree to avoid never
completing search
:returns: list of endpoints that match
"""
if region_id in regions_examined:
msg = _LE('Circular reference or a repeated entry found '
'in region tree - %(region_id)s.')
LOG.error(msg, {'region_id': ref.region_id})
return
regions_examined.append(region_id)
endpoints_found += (
[ep for ep in endpoint_list if
ep['service_id'] == service_id and
ep['region_id'] == region_id])
for region in region_list:
if region['parent_region_id'] == region_id:
_recursively_get_endpoints_for_region(
region['id'], service_id, endpoints, regions,
endpoints_found, regions_examined)
endpoints_found = []
regions_examined = []
# Now walk down the region tree
_recursively_get_endpoints_for_region(
region_id, service_id, endpoints, regions,
endpoints_found, regions_examined)
return endpoints_found
matching_endpoints = []
endpoints = self.catalog_api.list_endpoints()
regions = self.catalog_api.list_regions()
for ref in self.list_associations_for_policy(policy_id):
if ref.get('endpoint_id') is not None:
matching_endpoints.append(
_get_endpoint(ref['endpoint_id'], policy_id))
continue
if (ref.get('service_id') is not None and
ref.get('region_id') is None):
matching_endpoints += _get_endpoints_for_service(
ref['service_id'], endpoints)
continue
if (ref.get('service_id') is not None and
ref.get('region_id') is not None):
matching_endpoints += (
_get_endpoints_for_service_and_region(
ref['service_id'], ref['region_id'],
endpoints, regions))
continue
msg = _LW('Unsupported policy association found - '
'Policy %(policy_id)s, Endpoint %(endpoint_id)s, '
'Service %(service_id)s, Region %(region_id)s, ')
LOG.warning(msg, {'policy_id': policy_id,
'endpoint_id': ref['endpoint_id'],
'service_id': ref['service_id'],
'region_id': ref['region_id']})
return matching_endpoints
def get_policy_for_endpoint(self, endpoint_id):
def _get_policy(policy_id, endpoint_id):
try:
return self.policy_api.get_policy(policy_id)
except exception.PolicyNotFound:
msg = _LW('Policy %(policy_id)s referenced in association '
'for endpoint %(endpoint_id)s not found.')
LOG.warning(msg, {'policy_id': policy_id,
'endpoint_id': endpoint_id})
raise
def _look_for_policy_for_region_and_service(endpoint):
"""Look in the region and its parents for a policy.
Examine the region of the endpoint for a policy appropriate for
the service of the endpoint. If there isn't a match, then chase up
the region tree to find one.
"""
region_id = endpoint['region_id']
regions_examined = []
while region_id is not None:
try:
ref = self.get_policy_association(
service_id=endpoint['service_id'],
region_id=region_id)
return ref['policy_id']
except exception.PolicyAssociationNotFound: # nosec
# There wasn't one for that region & service, handle below.
pass
# There wasn't one for that region & service, let's
# chase up the region tree
regions_examined.append(region_id)
region = self.catalog_api.get_region(region_id)
region_id = None
if region.get('parent_region_id') is not None:
region_id = region['parent_region_id']
if region_id in regions_examined:
msg = _LE('Circular reference or a repeated entry '
'found in region tree - %(region_id)s.')
LOG.error(msg, {'region_id': region_id})
break
# First let's see if there is a policy explicitly defined for
# this endpoint.
try:
ref = self.get_policy_association(endpoint_id=endpoint_id)
return _get_policy(ref['policy_id'], endpoint_id)
except exception.PolicyAssociationNotFound: # nosec
# There wasn't a policy explicitly defined for this endpoint,
# handled below.
pass
# There wasn't a policy explicitly defined for this endpoint, so
# now let's see if there is one for the Region & Service.
endpoint = self.catalog_api.get_endpoint(endpoint_id)
policy_id = _look_for_policy_for_region_and_service(endpoint)
if policy_id is not None:
return _get_policy(policy_id, endpoint_id)
# Finally, just check if there is one for the service.
try:
ref = self.get_policy_association(
service_id=endpoint['service_id'])
return _get_policy(ref['policy_id'], endpoint_id)
except exception.PolicyAssociationNotFound: # nosec
# No policy is associated with endpoint, handled below.
pass
msg = _('No policy is associated with endpoint '
'%(endpoint_id)s.') % {'endpoint_id': endpoint_id}
raise exception.NotFound(msg)
@six.add_metaclass(abc.ABCMeta)
class EndpointPolicyDriverV8(object):
"""Interface description for an Endpoint Policy driver."""
@abc.abstractmethod
def create_policy_association(self, policy_id, endpoint_id=None,
service_id=None, region_id=None):
"""Creates a policy association.
:param policy_id: identity of policy that is being associated
:type policy_id: string
:param endpoint_id: identity of endpoint to associate
:type endpoint_id: string
:param service_id: identity of the service to associate
:type service_id: string
:param region_id: identity of the region to associate
:type region_id: string
:returns: None
There are three types of association permitted:
- Endpoint (in which case service and region must be None)
- Service and region (in which endpoint must be None)
- Service (in which case endpoint and region must be None)
"""
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def check_policy_association(self, policy_id, endpoint_id=None,
service_id=None, region_id=None):
"""Checks existence a policy association.
:param policy_id: identity of policy that is being associated
:type policy_id: string
:param endpoint_id: identity of endpoint to associate
:type endpoint_id: string
:param service_id: identity of the service to associate
:type service_id: string
:param region_id: identity of the region to associate
:type region_id: string
:raises keystone.exception.PolicyAssociationNotFound: If there is no
match for the specified association.
:returns: None
"""
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def delete_policy_association(self, policy_id, endpoint_id=None,
service_id=None, region_id=None):
"""Deletes a policy association.
:param policy_id: identity of policy that is being associated
:type policy_id: string
:param endpoint_id: identity of endpoint to associate
:type endpoint_id: string
:param service_id: identity of the service to associate
:type service_id: string
:param region_id: identity of the region to associate
:type region_id: string
:returns: None
"""
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def get_policy_association(self, endpoint_id=None,
service_id=None, region_id=None):
"""Gets the policy for an explicit association.
This method is not exposed as a public API, but is used by
get_policy_for_endpoint().
:param endpoint_id: identity of endpoint
:type endpoint_id: string
:param service_id: identity of the service
:type service_id: string
:param region_id: identity of the region
:type region_id: string
:raises keystone.exception.PolicyAssociationNotFound: If there is no
match for the specified association.
:returns: dict containing policy_id
"""
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def list_associations_for_policy(self, policy_id):
"""List the associations for a policy.
This method is not exposed as a public API, but is used by
list_endpoints_for_policy().
:param policy_id: identity of policy
:type policy_id: string
:returns: List of association dicts
"""
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def list_endpoints_for_policy(self, policy_id):
"""List all the endpoints using a given policy.
:param policy_id: identity of policy that is being associated
:type policy_id: string
:returns: list of endpoints that have an effective association with
that policy
"""
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def get_policy_for_endpoint(self, endpoint_id):
"""Get the appropriate policy for a given endpoint.
:param endpoint_id: identity of endpoint
:type endpoint_id: string
:returns: Policy entity for the endpoint
"""
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def delete_association_by_endpoint(self, endpoint_id):
"""Removes all the policy associations with the specific endpoint.
:param endpoint_id: identity of endpoint to check
:type endpoint_id: string
:returns: None
"""
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def delete_association_by_service(self, service_id):
"""Removes all the policy associations with the specific service.
:param service_id: identity of endpoint to check
:type service_id: string
:returns: None
"""
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def delete_association_by_region(self, region_id):
"""Removes all the policy associations with the specific region.
:param region_id: identity of endpoint to check
:type region_id: string
:returns: None
"""
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def delete_association_by_policy(self, policy_id):
"""Removes all the policy associations with the specific policy.
:param policy_id: identity of endpoint to check
:type policy_id: string
:returns: None
"""
raise exception.NotImplemented() # pragma: no cover
Driver = manager.create_legacy_driver(EndpointPolicyDriverV8)